class Convert {

static String toDayWeek(DateTime dateTime) {
    if (dateTime.weekday == DateTime.monday) {
        return "星期一";
      }else if (dateTime.weekday == DateTime.tuesday) {
        return "星期二";
      }else if (dateTime.weekday == DateTime.wednesday) {
        return "星期三";
      }else if (dateTime.weekday == DateTime.thursday) {
        return "星期四";
      }else if (dateTime.weekday == DateTime.friday) {
        return "星期五";
      }else if (dateTime.weekday == DateTime.saturday) {
        return "星期六";
      }else if (dateTime.weekday == DateTime.sunday) {
        return "星期天";
      }else{
        return "星期一";
      }
  }
}